Railway traffic controlling apparatus



June 2, 1931. H. A. THOMPSON ET AL 1,808,327

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Sept. 25. 1929 I I l I I I ll (izwlas Z 22190753 E. C. Jew/619W- ATTORNEY Patented June 2, 1931UNITED STATES PATENT QFFICE HOWARD A. THOMPSON, F EDGEWOOD BOROUGH, ANDCHARLES A. BROOKS, OF SWISS- VALE, PENNSYLVANIA, ASSIG-NORS TO THE UNIONSWITCH & SIGNAL COMPANY,

OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA RAILWAYTRAFFIC CONTROLLING APPARATUS Application filed September 23, 1929.Serial No. 394,402.

This invention relates to railway traffic controlling apparatus, andparticularly to apparatus for controlling trafiic in both directionsover a single stretch of track.

: One purpose of the invention is thepro- Vision of novel means forestablishing the direction of traffic within a single track sectionindependently of traflic conditions in any other track section. Theinvention further comprises the provision of means for selectivelybringing into action different devices in accordance with the directionof traffic, said means comprising relays having different releasingcharacteristics.

We shall describe one form of apparatus. embodying our invention andshall then point out the novel features thereof in claims. a

The accompanying drawing consists of a diagrammatic view illustrative ofour invention.

Referring to the drawing, the numeral 5 designates a section of railwaytrack. This section is provided with a track relay 6 having one winding6 connected across the rails adjacent one end of the section and havinga second winding 6" constantly supplied with alternating current fromterminals B and C of a source of energy not shown in the drawing. Atrack transformer 7 has its secondary connected .across the railsadjacent the opposite ends of the section, and the primary 7 of thetransformer is at times connected with terminals B and C as will bedescribed in detail hereinafter.- A. floating relay 8 has its winding 8connected to the leads of transformer 7, and winding 8" of this relay isconnected with terminals B and C. Relays 6 and 8 have differentreleasing characteristics; the relay 6 being designed to release itscontacts comparatively slowly in response to de-energization of itswinding 6, and the relay 8 releasing its contacts comparatively quicklywhen its winding 8 is de-energized. Relays possessing such releasingcharacteristics are well known in the art and need not be specificallydescribed. We utilize the difference in releasing characteristics ofsaid relays for selectively bringing into action different de- Vices inaccordance with the direction of movement of traflic in the tracksection 5. In this connection we have shown relays 9, 10, respectively,at the right hand end of the track section and other relays, 11, 12respectively, at the opposite end; and through our invention we areenabled to selectively energize'certain of said-relays (9 and 12, forexample) in response to the travel of trafiic in one direction in-thetrack section 5 and to selectively energize others of said relays (10and 11, for example) in response to traflic movement in said section inthe opposite direction.

When a train enters the track section from the right it de-energizes therelay 6. The floating relay 8 is not de-energized, however, until thetrain has reached some intermediate point in the section. While uponde-energization of relay 6 its armature will not drop instantaneouslyinto engagement with back contact 1 1 said armature will make suchengagement before the train has arrived at such point in the section asto de-energize the relay 8. Upon engagement of armature 13 with saidcontact 14 and while armature 15 if relay 8 remains in engagement withfront contact 16, a circuit is completed from terminal B through wire17, back contact 18 and armature 19 of relay 9, wire 20, contact element21 operable by the switch 22 and engaged with contact 23 when saidswitch is in normal position, contact 23, wire 23, back contact 14 andarmature 13 of relay 6, wire 24, armature 15 and front contact 16 ofrelay 8, wire 25, back contact 26 and armature'27 of relay 12, wire 28,relay 11,.wire 29, relay 10, and.

wire 30 to terminal C. The relays 10 and 11 are thereby energized. Assoon as the train has advanced a suflicient distance into the tracksection, the relay 8 opens, and its armature 15 is disengaged fromcontact 16, but the relays 10, and 11 remain energized by way of a stickcircuit comprising wire 31 connected to wire 24:, armature 32 and frontcontact 33 of relay 11, and Wire 34 connected to wire 28; said stickcircuit being closed upon the energization of relay 11 aforesaid. Itwill be apparent that the relays 10 and 11 are de-energized and thatenergized because the armature 15 of relay 7 8 will move out ofengagement with front contact 16 before armature 13 of relay 6 engagesback contact 14. Said train will, however, cause the relays 9 and 12 tobe energized; since upon de-energization of relay 8 and engagement ofits armature with back contact 35 while armature 13 of relay 6 engagesfront contact 36 a pick-up circuit for relays 9 and 12 is closed fromterminal B, through wire 37, armature 38 and back contact 38 of relay11, wire 39, back contact 35 and armature 15 of relay8, Wire 24,armature 13 and front contact 36 of relay 6, wire 40, wire 41, backcontact 42 and armature 43 of relay 10, wire 44, relay 9, wire 45,contact 46, contact element 47 operated by switch 48 and engaged withcontact 46 when said-switch is in normal position, wire 49, relay 12,and wire 50 to terminal C. Relays 9 and 12 therefore become energized inseries. At the expiration of the holding time of relay 6, this relayreleases, interrupting the circuit just traced, but current continuesflowing through said relays 9 and 12 by way of a stick circuitcomprising wire 51 connected to wire 24, armature 52 and front contact53 of relay 9, and. wire 54 connected to wire 40, saidstick-circuitbeing established upon energization of said relay 9. Also, in responseto de-energization. of the relay 6 the armature 55 thereof engages backcontact 56 and establishes a second stick circuit, from battery throughsaid armature 55 and back contact 56,.wire 57, ar-

mature 58 and front contact 59 of relay 9,

and wire 60 to wire 40, so that relays 9 and 12 will remain energizedwhen the train has proceeded far enough into the track section to allowrelay 8 to become energized. Current then flows from terminal B througharmature 55,, back contact 56, wire 57, armature 58, front contact 59,wire 60, wire 40, Wire 41, back contact 42 and armature 43, wire 44,relay 9, wire 45, contacts 46 and 47,

- Wire 49, relay 12, and wire 50 to terminal G.

The relays 9 and 12 are de-energized and the circuits restored to normalupon energization of relay 6 when the train leaves the track section. Atrain entering said section from the right cannot energize the relays 9and 12, because armature 13 of relay 6 is disengaged from front contact36 before armature 15 engages back contact 35.

It will thus be seen that we have provided for energizing differentrelays selectively and automatically in accordance with the direction inwhich trafiic moves in the track section 5. In other words, thedirect-ion of trafiic in said section is set up by the energization ofcorresponding relays, and we have provided for such setting up of thedirection of traffic independently of traffic movements in other tracksections. Relays 9, 10, 11, and 12, being responsive to the direction ofmovement of traflic,-ma'y be termed directional relays. The number ofdirectional relays employed may of course be varied as desired. Forexample, the relay 10 of the pair of relays responsive to movement oftrafiic'to the left may be omitted and wire 29 connected directly toterminal C. Similarly, relay 12 of the pair responsive to trafficmovements to the right may be omitted and wire 49 connected directly toterminal C.

We have shown wire 17 of the energizing circuit for relays 10 and 11connected to wire 20 through back contact 18 and armature 19 of relay 9;while wire 25 of said circuit is shown connected to wire 28 through backcontact 27 and armature 26 of relay 12. In this way a check is providedagainst any possibility of energization of relays 10 and 11 while eitherrelay 9 or 12 is energized. Likewise a check against thepossibility ofenergizing relays 9 and 12 while either relay 10 or relay 11 isenergized is provided by connecting wire 41 towire 44 through backcontact 42 and armature 43' of relay 10 and by connecting wire 37 towire 39 through armature 38 and back contact 38 of relay 11.

The relays energized in accordance with the direction of traffic in thetrack section 5 may be utilized in any suitable way to govern trafficwithin said section. One way in which said directional relays may becaused to control traflic is illustrated by way of example in theaccompanying drawing, wherein the relay 11 is shown controlling a motorcoder for supplying coded train control energy to the rails adjacent theleft hand end of the track section 5 while the relay 9 controls a motorcoder 66 for supplying coded impulses to the rails adjacent the righthand end of said section. Each of said motor coders as is well known inthe art,comprises an electric motor and means such as make and breakcams driven thereby for causing the opening and closing of contacts atdifferent frequencies. Thus, the contact element 67 is driven by motorcoder 65 to engage. contact 68 a given number of times per minute (180for example) while contact element 69 is operable by said motor coder toengage contact 70 at a different rate (as, for example, times perminute). Contact element 71 isoperated by motor coder 66 to engagealternately the contacts 72, 73, each of said contacts being engaged,

for example, 180 times per minute by said element 71; while contactelement 74 is operated by said motor coder 66 to engage contacts 75, 76alternately and at a different rate (8Q per minute, for example) thanthat at which contacts 72, 73 are engaged by contact element 71.

Assuming a train to enter the track section 5 from the left, relays 9and 12 are energized as previously described, and the energization ofrelay 9 closes a circuit through the motor coder 66 as follows; fromterminal B through wire 77, armature 78 and front contact 79 of saidrelay 9, wire 80, motor coder 66 and Wire 81 to terminal C. Each of theContact, elements 71, 75 of said motor coder is connected to acorresponding contact 82, 83 with which con tacts there cooperates anarmature 8 1 of a relay 85 responsive to traffic conditions to the rightof section 5. Since connections for rendering said relay responsive tosaid trafiic conditions are well known they will not be here described,and it is sufficient to note that the relay 85 is energized when trafiicconditions to the right of section 5 are safe and is de-energized whensaid con ditions are unsafe. If, at the time relay 9 is energized, relay85 is also energized, current will flow from terminal B through wire 86,contact 72, motor coder contact 71 (each time that said contact engagescontact 72), front contact 82 and armature 8 1 of relay 85, wire 87,back contact 88 and armature 89 of relay 10, wire 90, front contact 91and armature 92 of relay 9, back contact 94 and armature 95 of trackrelay 6, wire 96 and primary 97 of a code feeding transformer 97 toterminal C. The secondary of transformer 97 is connected across therails adjacent relay 6, and it follows that impulses of a frequencycorresponding to the rate of engagement of contact element 71 withcontact 72 are thus supplied to the rails adjacent the right hand end ofsection 5.

Connected in series with the coil 6 of track relay 6 is the primarywinding 98 of an impedance transformer 98, the secondary winding 98 ofwhich is connected by wire 99 to motor coder contacts73 and 76 so thatupon engagement of contact 73 by contact element 71 when armature 84 ofrelay 85 is engaged with front contact 82, said secondary winding 98 isshort circuited, and likewise when armature 84 en-' gages back contact83, said secondary is short circuited each time that contact element 74engages contact 76. It may be noted that each time that a circuit isclosed by contacts 71, 72 through thewinding 97 of transformer 97, thesecondary winding 98 of transformer 98 is open-circuited since contactelement 71 is at that time out of I engagement with contact 73. Theimpedance of the primary 98 of transformer 98 is thereby increased sothat any substantial flow of current through track relay winding 6 isprevented and said track relay remains inactive.

If, at the time relay 9 is energized, the relay 85 is de-energized,current is supplied by the motor coder to transformer 97 by way ofcontact 75, contact element 7 1, and back contact 83 and armature 84 ofrelay 85, whereby there are applied to the rails at the right hand endof the track section impulses of a frequency corresponding to the rateof engagement of contact element 74 with contact 75. Each time thatcurrent is supplied to transformer 97 by contacts 74, 75 the secondaryof transformer 98 is opencircuited, contact element 74 being at thattime out of engagement with contact 76, and the impedance of transformerwinding 98 is increased as aforesaid to prevent a flow of currentthrough track relay winding 6 sufiicient to bring said relay intoaction.

It will thus be seen that the energization of relay 9 may be utilized tocause impulses of coded energy to be supplied to the rails at the righthand end of the track section 5 in accordance with trafiic conditionsbeyond said end of the section. Said impulses may be received by theusual apparatus on the front of the train and caused togive-corresponding signals in the locomotive cab as is well understoodin the art. The train which has entered the track section 5 from theleft is thus apprised of traffic conditions beyond the right hand end ofsaid section.

When said train leaves the track section 5, the track relay 6 isenergized in response to energy supplied to the rails by transformer 7as soon as the secondary 98" of transformer 98 is short circuited by thecontacts of the motor coder 66; the impedance of the winding 98 inseries with track relay coil 6' then being sufficiently reduced by theshort circuiting of transformer winding 98 to permit the energization ofthe track relay. When said track relay is energized its armature 18 isdisengaged from back contact 14, thereby de-energizing those directionalrelays which were previously energized. Also, when the track relay isenergized its armature. 95 engages front contact 99 whereby transformerwinding 98 is maintained short circuited through a circuit which will beapparent from an inspection of the drawing.

Under normal conditions, that is, when section 5 is unoccupied, and alsowhen the section is occupied by a train moving from left to right,current is supplied to the primary winding 7/ of transformer 7, fromterminal B through back contact 101 and armature 102 of relay 11, andthence through wire 103 and primary 7 of transformer 7 to terminal C.When ;a train enters the track section from the right and thereby causesthe directional relays 10, 11 to be energized, armature 102 isdisengaged from back contact 101 and is engaged with front contact 104of the relay 11. The primary 7' of transformer 7 is now connected tobattery through the contacts of motor coder the circuit being fromterminal B through either contacts 68 67 or contacts 70--69 of the motorcoder (depending upon whether armature of relay 106 engages frontcontact 107 or back contact 108), thence through wire 109, back contact110 and armature 111 of relay 12, wire 113, front contact 10 1 andarmature 102 of relay 11, wire 103, and transformer winding 7 toterminal C. The relay 106 is responsive to traffic con ditions to theleft of track section 5; the connections for rendering said relay soresponsive being well understood in the art, and it being sufficient tonote that said relay is energized when said traffic conditions are safeand is de-energized when said conditions are unsafe. Thus, theenergization of directional relay 11 causes impulses of coded energy tobe applied by transformer 7 to the rails adjacent the left hand end ofsection 5, the frequency of said impulses depending upon whether currentis supplied through contact 67 or contact 69 of the motor coder, whichin turn is determined by the position of the armature of relay 106. Atrain entering the track section 5 from the right is thus supplied withcoded energy indicative of the traffic conditions to the left of saidtrack section. The energization of relay 11, in addition to connectingtransformer 7 to the motor coder contacts, energizes said motor coderthrough the engagement of armature 1141 of said relay with front contact115 so that said motor coder is brought into action concurrently withthe connection of the transformer 7 with one or the other of the sets ofcontacts controlled by the motor coder. In addition the energization ofrelay 11 breaks the circuit through coil 8' of the floating relay 8,this being accomplished by disengagement of armature 116 ofsaid relayfrom back contact 117. Thus, the track relay 8 is prevented from beingenergized by coded impulses supplied to the railsfrom transformer 7.When the train which has entered the track section 5 from the rightleaves said section, the track rel'ay 6 is energized by the firstimpulse of coded energy supplied to the rails by transformer 7 followingthe exit of said train; and thus the directional relays 10, 11 whichwere energized upon the entry of said train into the track section 5 arede-energized and the apparatus is restored to its normal condition.

The terms and expressionswhich we have employed are used as terms ofdescription and not of limitation, and we have no intention, in the useof such terms and expressions, of excluding any mechanical equivalentsof the features shown and described or portions thereof, but recognizethat various structural modifications are possible within the scope ofthe invention claimed.

What we claim is:'

1.7111 combination, a section of railway track, devices correspondingrespectively to directions of'movement of traffic in said .section andmeans comprising relays having different releasing characteristics forbringin one of said devices into action upon traffic movement in onedirection in saidsection and for bringing another of said (lo-- vicesinto action upon traffic movement in said section in the oppositedirection.

2. In combination, a section of railway track, a relay corresponding tomovement of traffic in one direction in said section, a relaycorresponding to movement of traffic in another direction in saidsection, and means comprising other relays having different releasingcharacteristics for energizing one or the other of the first mentionedrelays in accordance with the direction of traffic in said section. Y j

3. In combination, a section of railway tack, a relay having arelatively slow release characteristic connected to the rails adjacentone end of said section, a relay having a relatively rapid releasecharacteristic connected to the rails adjacent the opposite end of saidsection, and means jointly controlled by said relays. for setting up thedirection of traffic in either of opposite directions in said section.

1. In combination, a section of railway track, a relay having arelatively slow release characteristic connected to the rails adjacentone end of the section, a relay having a relatively rapid releasecharacteristic connected to the rails adjacent the opposite end of saidsection, devices corresponding respectively to directions of movement oftraffic in said section, and means controlled by said relays forbringing one of said devices into action when traffic moves in saidsection in onedirection and for bringing the other of said devices intoaction when traflic moves in the other direction in said section.

5. In combination, a section of railway track, a relay corresponding tomovement of trafhc in one direction in said section, a relaycorresponding to movements of traflic in another direction in saidsection, means comprising other relays having diiferent releasingcharacteristics and effective upon the entrance of a train into saidsection to energize a selected one of said first mentionet relays inaccordance with the direction of movement of said train, and trafficcontrolling means controlled by the'first mentioned relays.

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6. In combination, a section of railway track, a normally energizedtrack relay connected to the rails adjacent one end of said tracksection, a normally energized floating relay connected to the railsadjacent the other end of said section said track relay being releasedprior to said floating relay in response to travel of traific in onedirection in said section and being released subsequent to said floatingrelay in response to travel of traffic in the opposite direction in saidsection, a directional relay, means for bringing said directional relayinto action in response to release of said track relay while thefloating relay is closed, a second directional relay, and means forbringing said second directional relay into action in response torelease of the floating relay while said track relay is closed.

7 In combination, a section of railway track, a normally energized trackrelay connected to the rails adjacent one end of the track section, anormally energized floating relay connected to the rails adjacent theother end of said section, said track relay being released prior to saidfloating relay in response to travel of traffic in one direction in saidsection and being released subsequent to said floating relay in responseto travel of trafiic in the opposite direction in said section, adirectional relay, means for energizing said directional relay inresponse to release of said track relay while floating relay is closed,means for subsequently maintaining said directional relay energizeduntil the track relay is again energized, a second directional relay,means for energizing said second directional relay in response torelease of the floating relay while said track relay is closed, andmeans for subsequently maintaining said second directional relayenergized until said track relay is again onergized.

8. In combination, a section of railway track, a first directionalrelay, a second directional relay, means comprising other relaysconnected to the rails of said track section and having differentreleasing characteristics for energizing said first directional relay inresponse to trafiic movements in one direction in said section and forenergizing said second directional relay in response to trafiicmovements in the opposite direction in said section, and means forpreventing energization of either of said directional relays when theother is energized.

In testimony whereof, we have signed our names to this specificationthis 20th day of September, 1929.

HOWARD A. THOMPSON.

CHARLES A. BROOKS.

